Battery Tender '88

[p-cardriver]

I did a search but couldn't find an answer to this simple question...

I have a battery tender that plugs in through the cigarette lighter socket. But the key has to be one click on to get it to work. Is this going to cause any problems elsewhere in the car? I don't hear any noises (like a fuel pump or anything else) with the key in this position.

I could get clamps and attach to the battery, but that seems like a bit of a pain since I try to drive the car every week or 10 days this time of year.

Thanks,

Mike

1988 911

[wwest]

With the key "on" many (CDI, engine ECU) of the accessary loads are powered, trickle charge goes THERE.

My '88 has a battery vent tube that goes through a hole near the battery. Thread a positive wire through that same hole and use a simple connector. Use an inline fuse holder/fuse (~5A) near the battery post.

[curtisaa]

Go to Harbour Freight . they sell them for $ 6.99, and they work as well as the $ 50-$150 competition....

[Nine9six]

Originally Posted by curtisaa

Go to Harbour Freight . they sell them for $ 6.99, and they work as well as the $ 50-$150 competition....

Really?!? You gonna trust your Porsche electrical system to a $6.99 China POS trickle charger? $35-40 will purchase a descent trickle charger not sourced from China

[p-cardriver]

Thanks, guys.

I have a very good battery tender that I have used for years on a number of cars, but the 911 is the first one that had to be switched on to have a hot lighter socket. I don't want to do any damage to the car, but the tender will top up the battery and keep it topped even if there are other loads. It is just a bit slower than on the previous cars.

I may buy a $4 cigarette adaptor with alligator clips and just connect straight to the battery. Amazon seems to have the low price on that. But if I'm not doing any harm to the powered electronics, why bother?

[fitchesbass]

It takes two seconds to pop the hood. I say just get a normal trickle charger that goes on the battery. I don't trust the 'plug into cigarette lighter' approach for some reason.

Turning the ignition partially on to charge the battery is counterproductive. Thing may drain the battery instead of charging it depending on the ratings of your trickle charger.

[curtisaa]

Quote de curtisaa

Go to Harbour Freight . they sell them for $ 6.99, and they work as well as the $ 50-$150 competition....

Really?!? You gonna trust your Porsche electrical system to a $6.99 China POS trickle charger? $35-40 will purchase a descent trickle charger not sourced from China

We use them on $10M worth of cars
....just like I trust using my Iphone ( made in China ) with lots of personal info

[A horse with no name]

+1...For what it is worth, I used the connectors from a motor cycle tender battery charger ( had sold the bike).

The wires are wired directly to your battery and it has a short pigtail with a plug in at the end of it. This is the point whete you would plug in the wires from your charger. I use a dual battery charger come tender and it, as 'fitchrsbase' stated... To open your hood and unplug this type of settup is as easy as opening and closing your hood.

With this direct wire from the battery plugin fixed, you do not even see it. Alligator clips are OK but you will find the ' plugin ' much more convenient. Actually, you could make the setup from a couple of those pre wired pig tails with the plugins on them -> The ones that they sell for wiring a utility or boat trailer-< would work well as a connector that you would need if you choose to go this route. Any auto supply store should sell them.

Cheers!

[wwest]

Originally Posted by Nine9six

Really?!? You gonna trust your Porsche electrical system to a $6.99 China POS trickle charger? $35-40 will purchase a descent trickle charger not sourced from China

Just how is it you think a China POS (not that it is) could possibly overcharge any 911 Battery to the point of damaging the electrical system.

[wwest]

Originally Posted by p-cardriver

Thanks, guys.

I have a very good battery tender that I have used for years on a number of cars, but the 911 is the first one that had to be switched on to have a hot lighter socket. I don't want to do any damage to the car, but the tender will top up the battery and keep it topped

even if there are other loads.

I sincerely doubt that.

It is just a bit slower than on the previous cars.

I may buy a $4 cigarette adaptor with alligator clips and just connect straight to the battery. Amazon seems to have the low price on that. But if I'm not doing any harm to the powered electronics, why bother?

I would first check the "key on"/"engine off" system current flow before presuming your maintainer can support both symultaneous.f

[curtisaa]

Originally Posted by wwest

I would first check the "key on"/"engine off" system current flow before presuming your maintainer can support both symultaneous.f

the battery tenders that I see come into our storage ( www.privatecarstorage.co) that GT-3RS and GT-2RS , and GT-3 owner have purchased thru the dealers, are the cig lighter type. They work fine , but Porsche charges $ 300.00 for them.

As I previously said, $6.99 at Harbour freight does the same thing just as well.

[p-cardriver]

Thanks. My tender is a BMW branded cig lighter model that currently sells for about $65 at BavAuto. It is capable of 1.5 ams which seems to be enough to bring the battery up to full charge with the key in pos 1. My only concern is whether leaving the ignition key in that position could lead to electrical system or other? damage.

I plan to set up something connected directly to the battery when I can get around to it, anyway.

[Chuck.H]

If you're already turing the key to the first click, I'd go ahead and turn it further, starting the car. Then I'd go for a drive long enough to charge the battery. Sorry, couldn't resist. 80F here in Florida today, perfect Targa weather!

Chuck.H
'89 TurboLookTarga, 344k miles

[gtc]

Are you actually having battery issues? I wouldn't think you'd need a charger if you are driving the car every 7-10 days.

[samourai71]

I use this for a quick connect/disconnect.

Ring Terminal Harness - Accessories - Products - Batterytender.com

This way the car stays locked and the alarm on.

[p-cardriver]

On the 997 the battery would die in two weeks due to the loads that seem to be always on. So I've become paranoid. But I also recognize that a well tended battery will last a long time.

Are you actually having battery issues? I wouldn't think you'd need a charger if you are driving the car every 7-10 days.

[p-cardriver]

Assuming I need todo anything (key on causes some problem), I would wire up something like this to a cig lighter socket so I can plug in using my existing tender wiring/connector. Thanks.

I use this for a quick connect/disconnect.



Ring Terminal Harness - Accessories - Products - Batterytender.com



This way the car stays locked and the alarm on.

[Nostril Cheese]

Just think of all the problems solved if you disconnected the battery...

[samourai71]

Yes but some modern equipemnt like newer radios loose all their setting if disconnected too long. And the alarm won't work with no power ; )

[p-cardriver]

Or if I just sold the car!

Right now, I pull in to the garage, crack the pass window, slip the tender cable thru, plug it in the cig socket, turn the key, plug the tender into the wall and go inside. I'm willing to add another easy step but I'm not getting tools out every time I want to drive the car.

If I'm not causing any harm I will just continue with what I'm doing. If there is significant risk I will make a direct connector to the battery as discussed above.

Make sense?

Just think of all the problems solved if you disconnected the battery...